Converting analogue audio to digital using the 1/8" mic input

I have a bunch of old cassette tapes I want to convert to digital. The most convenient thing for me to use is this old digital voice recorder I have, (like these only older) which has an 1/8" mic input. Less convenient would be to use my computer’s soundcard since it’s a desktop and thus not portable, and I’d need to download additional software I believe. The voice recorder conveniently logs files which are then easily imported into my PC.

But when I tried to go from the RCA stereo out of the cassette deck (or actually from the preamp I believe) to the recorder’s mic input, it came out terribly distorted and wet. I’m guessing it has something to do with the way a mic signal is boosted by the device receiving it? Would the solution be then just to turn down the output level from the preamp? Am I completely off base?

The electrical specs of a mic input are wrong for a line-level signal. There are no circumstances under which it is ever OK to plug a line input into the mic socket. To do this properly, you will have to use your desktop computer and plug the tape deck, via a patch cord with RCA stereo plugs on one end and an 1/8" stereo plug on the other, into the line input on the sound card, and adjust the input level via the Windows Mixer.

Darn. OK, the computer it is.

But just for the sake of intellectual curiosity, is there really no way to attenuate/modify the line-level signal to make it appropriate for the mic in? Is the sound that travels through the 1/8" cable fundamentally different between the two? The same cable can be used to carry both kinds of audio, right? (or are there actually different cables for each?)

What exactly is that “wet” effect I heard?

The cables are the same or similar, but the input impedance and fixed, internal level of the mic input are much different from a line signal. The sheer magnitude of the signal in comparison to the output of a mic is just about staggering. There’s no way not to overload a mic input with a line signal. It is possible to buy an attenuator, but these are for professional setups. I don’t imagine anyone makes one for the home. The price of such a device and the limited use anyone would have for it negates mass production. Besides, it would still sound terrible, as a number of parameters have to be adjusted. It’s not worth trying! Just go with the RCA - 1/8" stereo patch cord.

If your computer and stereo are not close to each other, it’ll be best if you disconnect the tape deck from your system and set it up by your computer, and monitor the sound through the computer speakers.

Do you have recording software?

ETA: I’m not sure about the “wet” effect you describe, but I know that the distortion sounds nasty!

For recording software, try Audacity. It’s free and feature-laden.

Mic inputs on computers are designed for conferencing and such…horrble quality. Even if the impedence and levels were right, it would sound like crap.

Line input is the closest you can get to decent. When I had my studio, I ran an external rack box with a dedicated pro audio converter. Half-Life sounded great through the studio monitors BTW.

As for recording software…all the cool kids are runing Reaper these days.

http://www.cockos.com/reaper/

I don’t have recording software as of yet, but I will try audacity. Much thanks!

Oh, and by “wet”, I mean a certain sort of short, dense reverb, which I think better describes the distortion I heard than what you get from simply turning the recording levels way up high. There seems to be something else at play here than simply the overwhelming amplitude of the signal. It’s as if there’s so much sound coming in that it kinda gets shmeared out.

The only problem with a SM57/58 (mics which I like) is that they will not interface to the 1/8" jack on a laptop - they use XLR connectors. You will also need an (preferably a Firewire or USB) interface that includes a mic preamp. And that will push your budget way over.

I second the option for a decent mic with a USB a/d converter built in - a number of companies are doing them now, and you should be able to find one to suit your budget.

Si

I think you intended this post to go in the Buying a microphone thread in IMHO. I have notified the mods.

Thanks and :smack:

Si

You can get one of these: http://www.zzounds.com/item--HOSXVM4

Behringer makes extremely inexpensive mixers that might help you get from the casette to the recorder. Check out this one: http://www.zzounds.com/item--BEHXENTX502
You can attenuate the levels and it takes an XLR input, too.

Hope that helps!

That cable is for 1/8" output into a XLR input on a mixer. The XLR output of a SM57 won’t drive the Mic input of a laptop. You need a Mic preamp.

anyhow - this is the wrong thread for this discussion as noted above.

Si